Study Onadvanced Support Technique Withpipe-roof Intunnel
|School||Xi'an University of Science and Technology|
|Keywords||Tunnel Tube shed support technology Supporting Principle Numerical Simulation|
Tube shed support technology as an auxiliary methods tunnel excavation , to prevent tunnel collapse , to suppress ground movement control surface subsidence plays an important role , it can effectively solve the tunnels across the shallow large bias , weak broken , the flow of mud and the special geological conditions of the tunnel excavation problems , in addition to the the pipe roof advance support technology also has the advantage of reinforcement ahead of the long distance , high reliability, short construction period , pipe roof construction method is being more and more applications . In this paper in order to the pipe roof advance support technology for the study , the use of theoretical analysis , means of numerical simulation study , the main job of the following: (1 ) on the basis of the Common surrounding rock pressure theory , considering the tunnel depth , circumference rock conditions , excavation conditions and pipe roof as the the advance support structure characteristics of factors , obtained deep , shallow tunnels tube the shed by force load formula and based on the theory of elastic foundation beam pipe roof mechanics analysis model analytical solution pipe roof support structure deflection angle and moment equation . ( 2 ) application of soil arching effect principle derived formula of pipe the shed ring to the maximum allowable spacing . ( 3) the application of three-dimensional finite difference software (FLAC3D) ahead of pipe roof support structure numerical simulation of pipe roof arrangement type , the change in the length of the support , grouting and grouting thickness change of tunnel excavation impact analysis, calculation results show that the best arrangement type exists : pipe roof ; pipe-shed support increasing the length of the tunnel displacement ; the grout thickness increases tunnel displacement control is not significant , and there is an optimal grouting thickness . The above research results have reference significance for pipe roof support design theory and construction practice .